My pending U.S. patent application Ser. No. 08/228,884, filed Apr. 18, 1994, discloses a system which can be utilized to desalinate sea water. There are, of course, many prior art systems which utilize reverse osmosis to accomplish such objective. Typically, prior art desalinization systems are very expensive to operate and difficult to service. The system of my above-referenced pending U.S. patent application Ser. No. 08/228,884, filed Apr. 18, 1994, addresses this problem. The apparatus disclosed and claimed herein represents another approach to solving the problems inherent in the prior art.
The apparatus of the present invention utilizes a piston of a particular character in the apparatus. While reversible pistons per se are known in the prior art as part of hydraulic circuits, the character of the piston and related mechanism employed in the present system differs in regard to both structure and manner of operation. U.S. Pat. No. 4,793,153, issued Dec. 27, 1988 discloses a typical prior art hydraulic circuit employing a reversible piston to accomplish "energy recovery" in a mixed-phase motor in a refrigeration system.